Turn-in finger for box wrapping machinery



May 13, 1941. E m 2,241,962

TURN-IN FINGER FOR BOX WRAPPING MACHINERY Filed Feb. 27, 1940 $g 71 70 INVENTQR ERmasT G Rmcn' 1 BY @44 -d,

ATTORN EYS.

Patented May 13, 1941 TURN-IN FINGER'FOR BOX WRAPPING MACHINERY Ernest G. Rider, Philadelphia,'Pa., assignor to Stokes and Philadelphia, Vania Application February 27, 1940,

4 Claims.

This invention relates to turn-in fingers for box wrapping machinery.

In the art of applying a paper wrap to a cardboard box or the like it is conventional to superimpose a box upon a previously pasted wrapper and to cause the assembly to follow a downward movement during which successively the side flaps of the wrap are caused to adhere to the side walls of the box, the marginal edges of such side flaps are caused to be turned and lapped about the ends of the box, the end flaps are caused to be superimposed upon the lapped marginal edges of the side flaps and the end walls of the box, the upper margins of the side fiaps and of the joint end flaps and lapped side margins are caused to be turned over the upper edges of the box walls, and finally the turned upper margins are bent downwardly on the inner upper surfaces of the side and end walls of the box. Mechanism for the effective and proper turn-in of the upper margins of the side and end flaps and the lapped margins of the side fiaps, is the subject of the invention herein.

In the use of turn-in fingers according to past practices the box body was provided with a forming-block comprised of upper and lower relatively movable portions which were both initially within the box during the brushing or rolling of the side and end flaps and the lapping of the side flap margins into contact with the box walls, and the upper forming block was elevated perpendicularly of and out of the box a distance sufficient to permit the free reciprocation of turn-in fingers between the blocks. Such separation of the blocks allowed side turn-in fingers to advance transversely against the upstanding marginal portions above the upper edge of the box to initiate the turning-in of the side flaps in advance of the end flaps and in close synchronized relation thereto the end turn-in fingers advanced across the end walls of the box to bend the compound end flap over the upper edges thereof and at the corners upon the previously inturned side flap margins, and then pursuant to withdrawal of the turn-in fingers the upper forming block moved downwardly into the box brushing all of the inturned marginal edges downwardly into adhesive relation to the inner wall surfaces. As provided heretofore the side turn-in fingers have been thin, substantially planar horizontally guided reciprocating members and the end turn-in fingers have been similar and have had similar guided horizontal reciprocation difiering from the side fingers only in having elevated or embossed ends raised out of- Smith Company,

Pa., a corporation of Pennsyl-- Summerdale,

Serial No. 321,000

the plane of the main body of the end turn-in fingers to afford clearance to permit the end turn-in fingers to pass over the previously inwardly positioned side turn-in fingers. It will be appreciated that the embossing referred to is necessary when the boxes are of uniform depth as the fingers must then reciprocate in the same plane.

In order to minimize tearing at the corners it has been conventional to have the side turn-in fingers terminate inwardly of the interior end surfaces of the box, and in many cases the ends of end inturning fingers were exaggeratedly bent upwardly to afford extra clearance for the mass of wrap at the corners but with a consequent failure to effect sharp definition of the corners. As provided heretofore it has been conventional to provide the turn-in fingers as substantially rigid members having substantially fixed planes of horizontal movement, or have been otherwise so provided that the resultant wiping action across the upper edge of the walls of the box has been as a shearing action to exert a wiping motion across the upper surfaces of the walls of the box,

When it is realized that the corner of the assembled wrap elements comprises as many as four thicknesses of the material of the wrap and that the side turn-in finger itself constitutes a fifth lamination, it will be understood that the shearing motion of the end turn-in finger of the past frequently causes tearing of the material at the corner. It will also be understood that variations in thickness in the wrapper exert further variations in the responsiveness of the whole to bending distortion. It will be seen that the shearing motion of the turn-in fingers results in improperly turned corners and involves considerable waste.

It is among the objects of this invention; to provide improvements in turn-in fingers; to provide floating turn-in fingers enabling automatic adjustment to compensate for thickness or stiffness of a wrap; to provide improvements in box wrapping machinery; to provide improved methdds of wrapping paper boxes whereby inturned flaps are accurately folded to form smooth unbroken corners; to provide a novel turn-in finger assembly for wrapper flaps wherein the turn-in action is automatically varied as the thickness of the material varies; to provide means for increasing the output of wrapped paper boxes in a given time as compared to means heretofore in use; and many other objects and advantages tending above will become more apparent proceeds.-

In the accompanying drawing forming part of this description:

Fig, 1 represents as the description Fig. 3 represents a perspective of a box and wrap and the associated turn-in fingers just be-. fore the end turn-in fingers have been moved inwardly to complete the turning-in of the upper,

margins of the end flaps, with the actuating and supporting elements fragmentarily shown but with the forming block elements removed from the box, for clarity.

Fig. 4 represents a fragmentary corner of a box and wrap on an enlarged scale showing the plurality of thicknesses at the corner.

' Fig. 5 represents a fragmentary plan of a box and wrap prior to the inward folding motion of the fragmentary turn-in fingers, again with forming block elementsremoved for clarity.

Fig. 6 represents a fragmentary vertical section of the box and wrap with the forming block elements separated just prior to the advance of the turn-in fingers.

Fig. 7 represents asimilar fragmentary section with the end turn-in plate according to this invention contacting the end margins and showing in full lines the position to which they float.

Fig. 8. represents a similar fragmentary section marking the conclusion ofthe end turn-in finger movement, and its concluding mashing down movement as the upper forming block impinges thereon as it returns to'the box.

Fig. 9 represents a fragmentary transverse section through a completed assembly.

Figs. 10 and 11 represent respectively diagrammatic side elevations of modified forms of fingers, showing in dotted lines their positions of adjustments.

Referring to the drawing, a box, illustratively but not necessarily a cardboard box, is disclosed, comprising a bottom l0, side walls H and I2 and endwalls l3 and 14. The side and end walls illustratively have upper edges or surfaces IS in a common plane. It the walls may have different heights if desired.

A wrap is provided which comprises a bottom panel l6 arranged for adhesive mounting on the bottom H] of the box, side panels or flaps l1 and I8 and end panels or hand operation, the side panels [1 and I8 have the box, leaving upper edges or margins 22 exthe upper edges iii of the box side walls, the vertical end margins 23 of the side panels have been swung aboutv or lapped into" adhesive engagement with the end walls respectively, and the end panels have been swung up, into overlying adhesive relation to the end margins 23 and the end walls .upper margins 24 and the turned or lapped vertical margins extending above the respective up of the box, leaving per edges of the adjacent end walls of the box. The association of box and wrap to this point maybe in accordancew'ith the disclosure of my application on a non-stop box wrapping machine Serial No. 3l0,4'79, filed Dec. 22, 1939.

It will be recognized by those skilled in the art that an upper forming block comprising upper is contemplated also that flaps and 2]. By operation of a partof the machine (not shown) or by 2,241,962 v wiping block 25 and lower box unit 26 has been associated with the box in the development of the engagement of the box and wrap and that the final turn-in operation for all of the noted upper edges or margins of the side and end flaps or panels, is accomplished by withdrawing this wiping block 25 as shown in Fig. 6, leaving block 26 in the, box, in order to permit said margins to be bent inwardly about the upper edges of the box walls as is conventional. After such bending the moved axially down into the box to force the bent margins down about the inner upper edges of the box walls as shown in Fig. 9.

Referring to Fig. 4, a corner is portrayed on an enlarged scale showing that when the side wall margins 22 have been bent inwardly first as by the more or less conventional side turn-in fingers in their guided horizontal reciprocations, a substantial fold line 28 is formed about which the upper sidewall margin 22 is bent to form a reentrant layer 29 upon which the vertical margin upper edge 23 and the end flap margin 24 are subsequently superimposed. This involves four thicknesses at the corners, and When either of the advancing side turn-in fingers 21 is in position it in effect creates corner.

over the end wall, and with 'a horizontally positively guided advance it exerts a shearing stress on the paper wrap which frequently causes tearing of the covers and spoilage of the box.

It will be evident that in the case of heavy paper it is necessary to raise the plane of travel of the end'turn-in finger if the shearing stress factory wrapping of thebox.

Ihave found the prior' art of turn-in fingers can be obviated and uniformly successful, neat, tight and cilicientwrapping can floating end turn-in finger which adjusts itself to resistance to convert shear into a turning moment regardless of the weight of wraps used. A preferred embodiment of the invention is shown in Figs. 1, '2 and 3 in which the turn-in comprising the 30 having in a plane the prior art.

blocki25 has been withdrawn from an extra thickness at the that all 'ofthe disadvantages of be effected by providing a,

n floating end turn-in blade 30; starts forward in slightly spaced (vertically) re-r lation to this upper edge of the end wall of the in extreme oscillative position of the frame and box. At this juncture the turn-in blade 30 is assembly, and a turn-in finger mounted on the substantially at right angles to the wall M of frame. the box. 2. In turn-in fingers for box wrap-ping ma- Since the action of one blade 30 is a duplicate 5 chines, a two part forming block for the box, a of the other, and, as shown, both operate in synvertically floating horizontally reciprocating chronism this description will be directed to what turn-in finger arranged to adjust itself in achappens as one blade 30 operates. Thus as a cordance with the resistance encountered from blade 30 moves inwardly into contact with a fiap the wrap, the upper of said two part forming 24, it has to overcome the resistance of the mal0 block being arranged to contact with and to force terial to bending, which resistance varies in acthe floating turn-in finger downwardly toward a cordance with the thickness of the material. predetermined position relative to the edge of Therefore as the inward movement of the blade the box. 30 continues the pivotal action of the trunnions 3. A method of turning-in the upper edges of 36 allows the blade 30 to ride upwardly along the a wrap about the edge of an end wall of a box face of the fiap 24 thereby gaining leverage on without tearing the corners which comprises adthe fiap for a uniform and accurate turn-in of vancing a floating turn-in finger laterally against the flap above the top faces of the side fingers 21. the upstanding margin of the wrap as it exists In this connection it will be seen that the relaafter the advancement of the side turn-in finger, tion of the offsets 3| to the body of the blade 30 and in permitting it to float upwardly as a funcpermits the inward movement of the blade tion of the resistance of the wrap to turning without interference with the fingers 21. about the end of the box while advancing across In place of swinging on the short radius shown the end of the box, then in forcing an upper in Figs. 1, 3 and 7, it will be appreciated that as forming block downwardly upon the floating shown in Fig. 10 the entire assembly can swing 5 turn-in finger to compress the .turned wrap on a long radius to the same general effect, if against the upper surface of the end wall, the finger supporting device is so pivoted as to 4. A method of turning-in the upper edges of a obtain the result. wrap about the edge of an end wall of a box As shown in Fig. 11 similar results can be obwithout tearing the corners which comprises adtained when the entire finger assembly is ar- 30 vancing a floating turn-in finger laterally against ranged for vertical floating as a resultant of rethe upstanding margin of the Wrap as it exists sistance of the corners to bending. after the advancement of the side turn-in finger, In any case the shearing motion of the finger and in permitting it to float upwardly as a funcis converted into rolling or turning motion of the tion of the resistance of the wrap to turning finger because of its floating relation and the end about the end of the box while advancing across c posite flap is bent about and either comthe end of the box, then in forcing an upper pletely folded, or the descending block 25 forces forming block downwardly upon the floating it downwardly into contact with the upper surturn-in finger to compress the turned wrap faces of the flaps ag t e pp Wall 0 mash against the upper surface of the end wall, then the assembly into tight turned corners and ends. withdrawing the end turn-in finger and drop- I claim as my invention: ping the upper forming block downwardly 1. In turn-in fingers for box wrapping maagainst the in turned flattened marginal surchines, a horizontally reciprocable supporting asfaces and then into the box to wipe the marsembly, a supporting frame journalled in the ginal edge about the inner surface of the end assembly and having angularly divergent surwall of the box. faces arranged to abut the supporting assembly ERNEST G. RIDER. 

